A daily routine of 50 jumps could help save women from osteoporosis, according to a Nottingham University researcher.
Joan Bassey, senior lecturer in physiology in Nottingham's medical school, warns that one in four women will sustain a bone fracture as a result of osteoporosis, brittle bone disease, once they have passed the menopause. Prevention is vital, since there is no cure once the bones have become very brittle.
In an article in this month's issue of Annals of the Rheumatic Diseases, Dr Bassey assesses research into exercise, and concludes that while weight training, swimming, walking and cycling may have general health benefits, they do not help the fight against osteoporosis.
"Unless you're walking so fast that you're practically jogging, it doesn't seem to do much," she said.
But half an hour's daily jogging is offputting for many women, she acknowledges.
"By the time you've changed into trainers and a track suit, and showered afterwards, the whole thing takes about an hour."
Some studies, however, suggested that brief high-impact bone loading could increase bone mineral density, reducing the risk of fracture, and Dr Bassey's own research has revealed that only a few minutes' exercise a day can have a significant effect.
Her studies of pre-menopausal women in their late 20s and 30s have shown that daily jumping for only a few minutes produced an average 3 to 4 per cent increase in bone mineral density in six months, rising by more than 10 per cent in some of the women who had the lowest levels initially.
"Obviously, it's best done with a warm up and some stretches afterwards, but it needs no special clothes, you just kick off your shoes, and you don't get hot and sweaty," she said.
"The average height of the jumps was about eight centimetres. You don't have to do all 50 jumps in one long string, you can do them in groups of ten, for example. It takes about six minutes."
Dr Bassey is leading research into the effects of daily jumping on postmenopausal women, and said that while there were no results yet, she was "very hopeful" that they would be even more significant. She is also anxious to carry out a study on adolescent girls.
Dr Bassey stresses that the exercise regime is preventive and aimed at women who are still healthy. "This is if you don't have any back problems, or gammy knees. And if you had osteoporosis already, it would be disastrous."
But for those women able to benefit from it, 50 daily jumps "should be as automatic as cleaning the teeth".